Symbols of the Republican and Democratic parties. Credit: Comstock/Jupiterimages

The road to the 2012 U.S. presidential election begins in earnest today, with the start of the primary and caucus season. All eyes will be on Iowa, where Republican hopefuls will compete for a critical early win (presumably, they will have learned from the mistakes of Rudy Giuliani, a one-time front-runner who conceded virtually the entire first month of the 2008 primary season—a decision that killed his campaign). A win in Iowa is by no means a guarantee of a nominee’s ultimate success. Former Arkansas governor Mike Huckabee claimed the top spot in 2008, only to drop out of the race two months later. Still, Huckabee’s performance in Iowa allowed him to exert a surprising amount of influence in the early months of the primary season, and his rise to national prominence led to a spot as a regular contributor on the Fox News Channel. The contenders in today’s contest are:

Michelle Bachmann: The Tea Party darling has suffered anemic poll numbers since her peak in August 2011, when she won the top spot in the Iowa Straw Poll. A last-minute defection by her state campaign chair (who proceeded to endorse opponent Ron Paul) and the loss of a key “super PAC” didn’t bode well for the representative from Minnesota’s Sixth District.

Herman Cain: Yes, he suspended his campaign weeks ago, but the ballots were printed long before that. So expect the former Godfather’s Pizza CEO to collect a smattering of votes from those who miss the “9-9-9″ refrain that he brought to Republican debates.

Newt Gingrich: Well, he’s not going to be on the ballot in his adopted home state of Virginia, and the speed with which he blamed others for that mistake didn’t do much to boost his flagging poll numbers. Newt needs a solid performance in Iowa to reclaim any of the momentum that he enjoyed through the last few Republican debates, but a damaging barrage of negative campaign ads from his opponents made that possibility seem increasingly unlikely.

Jon Huntsman: Despite poll numbers that rarely topped single digits, Huntsman remained a favorite of moderate Republicans. Polling numbers in New Hampshire indicated that his position was much stronger with independents (who are allowed to cast ballots in that state’s primary), but Iowa’s closed caucus system promised to do no favors for the former Utah governor.

Ron Paul: The former Libertarian presidential candidate appeared to be a stronger campaigner in 2012 than he was in 2008, when his core of fervent supporters failed to translate into success in the primaries. Despite having spent two decades in the U.S. House of Representatives, Paul retained a certain degree of credibility as a Washington outsider, and widespread disapproval of Congress actually seemed to bolster his chances. Paul has traditionally been a strong performer in closed caucuses and straw polls, so a first or second place finish in Iowa would not be entirely unexpected.

Rick Perry: Well, that honeymoon didn’t last long. Perry’s disastrous performances in Republican debates doomed his status as a front runner, and pundits quipped that his failure to make the ballot in Virginia was a result of him losing track of the number of signatures he needed after he got to two. Still, he retained a strong appeal for Evangelical voters and climate change skeptics, and unlikely comebacks are a fixture in American politics (see Bill Clinton in 1992 campaign).

Mitt Romney: Widely regarded as the ultimate favorite to win the nomination, Romney is well-funded and well-placed to win in Iowa. While unable to generate the “brand loyalty” of a candidate like Paul, Romney has essentially been campaigning for the nomination since 2007, and his status as “nominee-in-waiting” has been challenged, but not usurped.

Rick Santorum: A last-minute popularity boost ahead of the caucus (because, presumably, every other candidate had had a chance to take the lead, and now it was his turn) saw Santorum jump into third place in opinion polling. Surprisingly strong showings in some of the later debates—as well as declining support for Perry and Gingrich—elevated the former Pennsylvania senator to within striking distance of Romney.